The Copenhagen Wheel turns any bicycle into an electric hybrid

The heyday for electric vehicles was way back in the early ’30s — the 1830s that is. By 1867, a workable two-wheeled electric cycle was on display at the Paris World Exposition courtesy of Austrian inventor Franz Kravogl. In the early 1900s, the premier bike shops of the day, namely that belonging to the Wright brothers, were already building air-worthy contraptions. While Miss Gulch’s tornado-powered flying bike from The Wizard of Oz somehow failed to materialize for us, our consolation prize — an electric hub-motor plug-in for our smartphones known as the Copenhagen Wheel — is finally here.

The device is a swap-in style package that replaces your standard issue bike wheel with 350 watts of hill-busting, regenerative power-harvesting awesomeness. Not since the invention of the electric toothbrush has there been such smooth integration of manual and machine power available to us. The beauty of the design is that all the hardware — motor, control, and batteries — are squeezed into a pancake that still manages to fit between the back forks of a traditional bike. Therein lies the magic. Once you plug the enhanced bike into your phone it becomes your new bionic best friend, intuitively sensing how fast you want to go from the effort applied to your pedals much like the Segway responds to your lean.

What has made the electric bike motor such a unique challenge over the years is that while the demands for light weight in a slim footprint naturally suggest a motor-in-hub power design, getting enough low-RPM torque to the wheel without sophisticated and massive planetary gearing has always been problematic.

Flat motor designs (actually called pancake motors) have been around for a while, but have never been all that great as far as performance. Precision control of three-phase DC brushless motors, as exquisitely used in the Copenhagen Wheel, has now been perfected to such an art form that near-impossible wizardry Tesla himself could have barely imagined is now available for everything from simple computer fans to electric tanks.

From the technical specifications above, we can see that while the Copenhagen Wheel is no beast, it does have an impressive array of features. Not least among them is a forthcoming SDK that hopefully will allow some customization. Once hackers can put a slave wheel on the front forks so that total power is more in the single horsepower range, then who knows, maybe even Americans will buy a few. Instead of the tandem concept, mount the two wheels in parallel, then suddenly a ZRT (zero radius turn) wheelchair design becomes interesting. With a little more imagination, spin a re-geared hub 90 degrees and stick a small prop on the end, and human-powered flight designs may get a much needed enhancement.

The main hurdle to widespread adoption of this kind of device is probably not technical, but rather legal. Every jurisdiction likely has its own interpretation of what constitutes license-worthy motive power. At a price point of less than $1000, many will hopefully be ready to find out for themselves what the Copenhagen Wheel will make possible.

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Did I miss the ‘range’ of said device? Seems pretty important if it only goes a few miles…

conservativemind12

I’m sure a couple of these strapped to your wheel chair would be awesome.

You spelt ‘dying’ wrong on your avatar.

Bob Céitinn

A couple of “corrections.” While it is proper to refer to a bicycle’s front fork (singular), bicycles do not have a back fork, they have stays. Whether seat or chain theses are properly called stays. Saying something “manages to fit between the back forks of a traditional bike” is wrong in both engineering and grammatical senses.
Municipalities already have laws governing the who, what and where of electric bikes and scooters.

jhewitt123

Go away, back forks is better. I don’t believe laws in this case are comprehensatory.

Ron G.

You must be the guy who comes in the shop and says, “My tire is wobbly” when you mean your wheel is out of true.

And, even if you insist on referring to the rear triangle as the back fork, it’s still singular. How many forks do you see back there?

jhewitt123

Yes, and you must be the guy that puts on a pair of leotards and thinks he turns into a car

Ron G.

Why would I do that? Being a cyclist is much more satisfying than being a driver, and I have no desire to downgrade.

Oh, and comprehensatory isn’t a word, comprende?

jhewitt123

In other words, yes, the slots for the rear tires as clearly shown above are forked, and yes there are 2 of them (other side not seen), and so thank you John for your efforts to set our silly industry straight on terminologyhttp://en.wikipedia.org/wiki/Fork_end

Bob Céitinn

Okay, you write an article on something you know only partially understand. You use the wrong nomenclature and catch a little flack. So you link to an article that you seem to think justifies the usage, but doesn’t. A few insults and a neologism latter you’re still defending a poor choice of words, albeit with a final flourish of irony. Does that make you feel superior? The bike shown has track style drop outs, these are only rarely referred to as fork ends, and never as back forks. Are you saying that the wheel only works on track bikes? No? Then its slip the infernal contraption between the rear stays of a bike and it’s off you go. Your suggestion that I go away… Okay, this is me fəcking off.

jhewitt123

Bob, I do appreciate your analysis. What you see as a final flourish of irony, I see for the fundamental truth you hoped it belied; the incrementally stagnant world you know so much about is limited as much by the intolerance of the narrow minds that operate within it as by the stupid terminology which just put you in the position of having to call a fork a not-fork. If you get in the face of an old man who knows how to use a cane don’t be surprised if you get hit in the nose. As for your continually dismissive comments as just given below to the gentleman commenting on the sway/swing arms, what would you call this device, a swing arm or a jackshaft?: https://twitter.com/jhewitt123/status/529345531559313408/photo/1

Brian Benghazi Piper

Could also be sway arms

Bob Céitinn

No. There are swing arms and there are sway bars, but there are no sway arms. Nice try though.

BtotheT

#Weeds

Cosmin Watson

Yeah, that guy is the inventor:))

dc

The price is too high. You can buy a complete electric bike for less than the price of that motor, and a really good electric bike is about the same price as the motor+ the bike (figure a top line model is around 2k).

massau

While having the right brakes, tires and reinforced frame while being preset for the local regulation e.g. 25km/h in most of Europe.

i also wonder who thought it was a good idea to add extra mass to the moving part of a wheel. it doesn’t sound like a good idea to have extra momentum which will just eat some extra battery power and slow bike bike its acceleration.

jhewitt123

Good point, maybe they could apply power to the rim insert via a brush system like the old DC motors

massau

most DC bike motors are PWM controlled and have the electrical connection on the stator just like your computer fan motor but scaled up.

jhewitt123

“POWER” I said, as in transmit the DC battery power from a frame mounted pack via a single hot brush lead and another ground brush for the return, so that there is less unsprung wheel weight.
No wonder this industry has scarcely improved on the Wrights in 100 yrs

massau

yes i under stood what you meant, but i just mentioned how it works on normal electrical bikes (stepping motor).
The brushes give extra resistance which isn’t there when you use an active stator instead of a passive one (normal brush DC motor).

jhewitt123

I would expect traditional steppers on bikes.
If this resistance is actually a concern, either inductive coupling (not efficient) or high voltage electric spark gap transmission could be tried eh?

massau

sorry, i miss mixed up a term i meant a servo motor not a stepping motor (which are exactly the same but the stepping motor has more “steps”). with the brushless motor there is no need to add the windings to the rotating part so the weight is only dependable off the magnets used.
but a much better way to build an electrical bike is adding the motor at the drive chain instead of the hub. this would enable the use to physically disconnect the motor when it isn’t used. while keeping the weight in the middle.

high voltage spark gap is also very inefficient, because it has to be converted and its unsafe for the user, its a transmission of >100W.

Dave Marques

I agree the price is to high.

Sam Hsu

The price is good for what it can do, can be installed on any bike in minutes, SDK for all kinds of blue tooth phone apps. Battery can swaped in seconds. It’s total automated with just pedal. An ebike less than $800 is a piece junk with lead acid battery, motor last maybe a year, and weights over 60 lbs. I rather pay $800 and put it on my existing “bikes” than buying “one” over $2000 ebike. Swap it on a beach cruiser, mountain bike, recumbent bike, comfort bike…etc. I’m sure a developer will come up will a over speed app to tune it over 20 mph. If you use it for daily commute and transport $800 is reasonable.

orwell

i was totally interested until i saw the $800 price tag. :(

http://www.funstufftosee.com Dozerman

I’m still a little suspicious of designs like this. In a braking design such as a hybrid car, you’re taking energy that would ordinarily be wasted and putting it toward forward momentum at a later time. In this design, you’re stealing energy that you’d use in a coast or in backpedaling and (relatively inefficiently) storing it for later use. I can see where it would be useful in hilly terrain, evening out the difference between uphill and downhill, but this still isn’t as efficient as a hybrid vehicle.

Bitterbear

So It can be controlled via smartphone and it has power breaks.. I like where this is going.

massau

excactly what the maffia asked for.

Adam

hello weeds?

http://www.korioi.net/ Korios

I am disappointed at the price, it screams “R&D ROI”…

Denver Catboy

Could you explain how?

$799.95 is expensive, yes, but it doesn’t seem like that’s R&D.

The battery is 48v x 6.1ah. That alone is $150 to $200, and that’s from cheap Chinese distributors.

The electronics themselves, with the logic needed to handle running the bike wheel with or without the smartphone should easily be worth at least $100, and add in the 350w motor winding, and I could easily see $400+ (A really high quality equivalent motor from Bionx is $800+).

You can get cheap motors, of course. A Crystalite M3525R is $350, but it’s JUST the motor — no electronics, no controller, just a dumb collection of wires that needs something intelligent to make it turn. It’s also a 14lb monstrosity, which hurts when it’s unpowered. If I’m reading this right, the entire motor system, including battery, motor, controller, and extra electronics, weighs a pound less. A combined Motor, Controller, and Battery would run 8lbs extra for a 36v, 9ah battery, 1lbs for a 20A controller, and the previously mentioned 14lb motor, making the entire kit 23lbs. You’ll need that 600W for that weight.

That said? I think you’re getting an awful lot packed into that $799 pricing. Mind you, it may not be worth $799, if they source cheap Chinese parts (in that case, shame on them), but if they’re using good quality parts, it may be priced so low your ROI will be negative.

I would like to bike commute to work more without needing to shower when I get there. This seems like the perfect solution. But… I’m a big guy. I’d like to know what limitations there are on the size/weight of the rider.

I’d also like to know if you can buy just the external casing portion (with all its internals) and mount it to the rim of your choice. I guess even if they don’t sell it that way you could probably do it yourself. Hopefully that would not void a warranty.

Richard

I bought an ebike from Chicago Electric Bicycles in 2012 and it has run like a champ ever since. I mostly use if for commuting to work. An ebike is a great investment.

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Brigita

I am thinking of replacing my bike with an electric one. I don’t know much about them though. They look really cool elektriniai dviračiai

Junior Hebert

WHERE DO YOU BUY COPENHAGEN BICYCLE WHEELS ???? I can’t even find a legit web site,always goes to something else,can’t find anywhere to buy one.

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